After several weeks of remote-control repair work, the Hubble Space Telescope is back in action, and is once again taking breathtaking images of distant galaxies. Today, NASA released an image which it called a “perfect 10″ because the paired galaxies resemble the number 10. The picture was released this morning by NASA to demonstrate that the observatory’s workhorse Wide Field Planetary Camera 2 is on the job again [Baltimore Sun], and a happy NASA press release added that the camera scored a perfect 10 for both its performance and the beautiful results.

The image shows a pair of galaxies, known as Arp 147, which are about 400 million light years away from Earth. The two galaxies are thought to have collided, and the image shows that aftermath. The blue ring was formed after the galaxy on the left passed through the galaxy on the right. Just as a pebble thrown into a pond creates an outwardly moving circular wave, or ripples, an outwardly propagating ring of higher density was generated at the point of impact of the two galaxies, astronomers explained. As this excess density collided with outer material that was moving inwards due to the gravitational pull of the two galaxies, shocks and dense gas were produced, stimulating star formation [SPACE.com].

The telescope was dormant for one month after a malfunction brought its work to a screeching halt in late September, when a device needed to collect and process data from the telescope’s science instruments failed. In an attempt to revive the probe, NASA successfully switched the device over to a back-up “B-side” about two weeks ago [New Scientist]. But more glitches occurred partway through the switch, and on October 16 the Hubble sent itself back into “safe” mode to give engineers a chance to look at the problems. By last Saturday NASA had finally worked out all the kinks, and switched the cameras back on.

The backup B-side data collector is now doing all the essential work related to translating data collected by the telescope into a form that can be transmitted to Earth. A third data formatter is currently at the Goddard Space Flight Center being prepared for delivery to Hubble on the upcoming repair shuttle mission [Washington Post]. The Hubble repair trip was originally scheduled for October, but was postponed when the recent glitch occurred so that NASA could gather spare parts to send up with the space shuttle; NASA now says the repair mission may happen in February or May.